Control units which are used to control the distribution of electric current to a plurality of electric loads, such as a number of motors, from a central location, are generally housed in compartmented structures called control centers. Such control centers are formed of a group of individual control center sections each of which includes a plurality of cells or compartments wherein the control units are installed. Each control center section houses a number of control units vertically stacked one on top of the other. To facilitate wiring and servicing, control centers are provided with main horizontal bus bars which extend across the upper portions of all of the individual control center sections and which are connected to deliver current from a supply to groups of individual vertical bus bars in each control center section. Electrical current is supplied to the control center via the horizontal bus bars and is distributed through the vertical bus bars that run the length of each control center section. The vertical bus bars in turn deliver the current to the control units within the individual control center sections through separable jaw-like connectors which make contact with the vertical bus bars.
Power cables which are coupled to the opposite end of the jaw-like connectors could rotate creating unsafe electrical spacings to the motor control unit enclosure. Elaborate features, such as double bolts, shouldered lugs or embossed connectors, could be added to the power bus connectors to provide anti-rotation, however these features would add significant cost and complexity to the assembly. Therefore, there is a need to provide a device which is simple while preventing the wire cable from rotating.